Documents Needed to Bid on Public Tenders in Spain (2026)

This guide is the checklist behind a Spanish bid: every document and step, in the order a tender asks for them, with who can lawfully do each one. For how Spanish procurement works overall (thresholds, procedures, how bids are assessed, getting paid), see How to bid for public contracts in Spain.

Before you bid

1. Your company’s tax number (NIF). Every certificate, register and signature in a Spanish tender is keyed to the company’s NIF, issued by the AEAT. Spanish companies already have one.

Cost and validity: free; permanent.
Who does it: a gestor or asesor files modelo 036 as the company’s representative, under a notarised power. You sign that power before a notary and supply the registry extract and the details of your beneficial owners.
From abroad: a non-resident company obtains an “N” NIF through modelo 036, with apostilled and sworn-translated incorporation documents. It is optional if you have no Spanish tax obligations (see NIF and signature under foreign companies, below).

2. Register on PLACSP, or on the regional platform. A registered economic-operator user on contrataciondelestado.es lets you subscribe to tenders, ask questions, receive communications and use the bid preparation tool. Buyers in seven regions host their tenders on their own platforms instead: Catalonia (with its sobre digital), the Basque Country, Madrid, Andalusia, Galicia, La Rioja and Navarra.

Cost and time: free, the same day; the PLACSP user stays valid indefinitely.
Who does it: users are individuals identified by an email address, so your adviser can register as the preparer (preparador). The company data (NIF, legal name) must be real, and the communications email must be one you control: official notifications go there.
From abroad: the same; a company without a Spanish NIF chooses the “Otros” identifier type.

3. A notarial power for the person who signs (escritura de poder). Whoever signs the offer in the PLACSP tool must be able to bind the company. If that person isn’t a registered administrator, they need an escritura de poder granted before a notary.

Time and validity: 1–3 days in Spain, longer abroad; valid until revoked.
Who does it: a lawyer drafts the scope (signing bids, guarantees, joint ventures, and the special clause needed for an FNMT certificate); your legal representative grants it before the notary. The person named, the apoderado, can be one of your employees or a lawyer acting under their own identity.
From abroad: granted before a foreign notary with an apostille and a sworn translation, or before a Spanish consul. If you have a Spanish branch, it must also be registered in the Registro Mercantil.

4. An electronic certificate the platform accepts. The PLACSP tool signs documents and envelopes with AutoFirma, using certificates from providers recognised by the State’s @firma platform: FNMT, DNIe, Camerfirma, ANF, Izenpe and others.

The usual choice: the FNMT certificate for a representative of a legal person, €14 plus taxes, valid 2 years. Your representative requests it online and then accredits identity online (with an existing qualified personal certificate), at Correos, or at an AEAT or CNMV office, bringing registry certificates no older than 15 days (and the notarial power with the special clause, for a voluntary representative). The certificate is ready about an hour after accreditation.
Before your first bid: check that the apoderado’s certificate validates at valide.redsara.es and install AutoFirma.
Who does it: only the person named in the certificate requests and holds it. A lawyer who is your named apoderado can obtain their own representative certificate for your company in the same way.
From abroad: the FNMT route needs a Spanish NIF for the company and, in practice, an NIE for the representative. Otherwise, test your own qualified certificate at VALIDe. If it fails, open a ticket with CAID, the platform’s support desk, and use the “Otros” route: submit unsigned in the tool, sign the documents by other means and tell the buyer.

5. ROLECE, and classification for works. ROLECE records your capacity, representation, solvency and classification once for every public buyer, and is mandatory for the simplified open procedure. Classification is needed for works of €500,000 or more. ROLECE is free, and no fee is published for classification. The full process is in our guide to ROLECE and contractor classification; for the paperwork:

ROLECE: a lawyer or adviser assembles your deeds, powers, accounts in XBRL and licences; the application is signed online by your representative, or by a lawyer who is your registered apoderado with their own certificate. A decision can take up to 3 months, but an application filed before a bid deadline, with its receipt and a sworn statement, is accepted. Changes must be reported. Catalonia’s RELIC and other regional registers work the same way, but count only with that region’s buyers and its local bodies.
Classification: compiled from works certificates (signed by the works director and endorsed by your client), staff, machinery and accounts, and signed through AutoFirma. Allow up to 6 months. EU and EEA firms are exempt; non-EU firms must be classified themselves, even inside a joint venture.
Keeping them alive: an annual economic-solvency declaration, filed before 1 September for a calendar-year company, and a technical update every 3 years. An accountant prepares the figures from your deposited accounts; your representative signs. Missing a filing suspends the classification.

With your bid

6. The DEUC or a declaración responsable. Your bid carries a self-declaration of capacity, solvency and the absence of exclusion grounds: the DEUC in most procedures, or the declaration built into the buyer’s forms. It is free and valid for that tender only. In a joint venture, each member files its own DEUC, and so does each company whose capacity you rely on.

7. The declarations you sign.

No prohibition to contract (article 71 LCSP): that neither the company nor its directors are barred. Part of the DEUC; it can also be made before a notary, an administrative authority or a qualified professional body.
Disability quota and equality plan: companies with 50 or more workers declare that they meet the 2% quota of employees with disabilities and have an equality plan.
Submission to Spanish courts (foreign bidders): a declaration waiving foreign jurisdiction for any dispute.

Your adviser drafts them; your apoderado signs each one with their own certificate.

8. Preparing and sending the offer in the PLACSP tool. The Herramienta de Preparación y Presentación de Ofertas is a desktop tool that separates three roles: the preparer (comercial), the signer (apoderado) and the sender (mensajero).

The preparer fills in tab 02-Licitador (the apoderado’s name, NIF and the nature of the power) and tab 03-Autorizaciones (your consent for the buyer to consult the AEAT and TGSS directly), attaches the DEUC, the technical document and the price to each lot and envelope, and exports the file.
Your apoderado imports it, reviews it, and signs every document and envelope with their own certificate.
The send: your apoderado sends it, or exports the fully signed offer so that someone else performs only the send. Download the receipt (justificante). If the upload fails, the tool records an electronic fingerprint (huella electrónica), and the complete offer must reach the buyer within 24 hours.
From abroad: if your certificate wasn’t validated, use the “Otros” route and sign the documents by other means.

9. A bid guarantee, where the tender asks for one. It is exceptional and never used in the simplified procedure. A bank issues an aval, or an insurer a seguro de caución, on the buyer’s model; it is deposited at the Caja General de Depósitos or the buyer’s treasury, as the tender says, and lasts until award or formalisation. You sign the facility with the bank or insurer. Guarantees from EU banks may be accepted if the tender allows; usually a Spanish-registered bank or branch is used.

10. A joint-venture commitment (UTE). Companies bidding together sign a compromiso de constituir UTE naming the members, their shares and the representative. A lawyer drafts it; each member’s apoderado signs it with their own certificate in the PLACSP tool. The UTE deed is executed before a notary, for a notarial fee, only if you win.

If you’re proposed as the winner

The buyer asks the proposed winner for evidence, and you have 10 working days to provide it together with the performance guarantee. If a company is in ROLECE, the register already covers what it records.

Document	Issued by	Who can get it for you	Valid for	What only you do
Tax certificate (certificado de estar al corriente, for public-sector contracting)	AEAT	A gestor or asesor, with their own certificate, once you register their authorisation in the AEAT Registro de apoderamientos; or the buyer consults it with your consent	Generally 12 months unless circumstances change; the tender may want a newer one	Register the authorisation (online, at an office or by notarial document)
Social Security certificate	TGSS	A graduado social or gestor, as your registered apoderado or RED-authorised user; usually issued immediately online, and it must name the contracting body’s NIF	—	Register the professional with the TGSS
IAE registration (registration and last receipt, or exemption declaration)	AEAT or the local council	A gestor, under the same AEAT authorisation	—	Grant the authorisation
Registry evidence (nota simple or certificación)	Registro Mercantil	Ordered online by anyone: the register is public	Same day for a nota simple, a few days for a certificate	—
Turnover and accounts	Registro Mercantil (deposited accounts) or your auditor	An accountant or auditor prepares the statement	Your last closed year or years	Sign any turnover declaration
Certificates of good execution and the list of similar contracts	Your former clients	Requested from your clients for you	—	Sign the list of works or services
Liability insurance, if the tender asks	An insurer authorised by the DGSFP	A broker or insurer	Annual	Sign the policy and pay the premium

Proof of tax and social-security compliance matters because arrears are an exclusion ground (article 71.1.d LCSP). For technical solvency, works contracts look back 5 years (10 years for 22 work subgroups since April 2026) and supplies and services 3 years. Companies that don’t deposit accounts prove turnover with their legalised accounting books.

When the tender asks for them: quality and environmental certificates (ISO 9001, 14001, 45001 or EMAS) from an ENAC-accredited body, or one accredited in another EU state.

Before the contract and the first invoice

The performance guarantee (garantía definitiva). Lodged within the same 10 working days, as an aval from a bank or a mutual guarantee society (SGR), a seguro de caución from an insurer, or cash or public debt. At the State level it is constituted electronically at the Caja General de Depósitos (Real Decreto 937/2020); otherwise at the buyer’s treasury. You send the deposit receipt (resguardo) to the buyer. It stays in place until the guarantee period ends. You sign the facility and pay the commission; a foreign company may need a Spanish bank or branch.

The contract (formalización). Signed by your legal representative or apoderado with their own certificate, after the standstill of 15 working days where it applies.

REA registration (construction). Firms that contract or subcontract on building sites must be in the Registro de Empresas Acreditadas (Ley 32/2006, Real Decreto 1109/2007), kept by the labour authority of the region where the company is registered and valid nationwide. A gestor prepares it and your representative or an apoderado files it online with a digital certificate. It takes about 15 working days, lasts 3 years, and is renewed in the 6 months before expiry. Foreign construction firms register too, in the region of their first works.

E-invoicing through FACe. Invoices to public bodies go through FACe or the regional hub, in Facturae format, foreign companies included. It is mandatory for invoices over €5,000, and many buyers require it for all. Your accountant issues them, signed with the company’s certificate or an issuing agent’s.

Who does what

Step	Who can do it	What only you do
NIF (modelo 036)	A gestor or asesor, as your representative	Sign the notarial power; give beneficial-owner details
PLACSP or regional platform registration	Your adviser, as preparer	Control the communications email
Notarial power for the signer	A lawyer drafts; a notary grants it	Your legal representative appears before the notary
Electronic certificate	Only the person named in it	Request and keep it; never share it
ROLECE, classification and the annual declaration	A lawyer, accountant or adviser assembles the file	Your representative signs, or a lawyer who is your apoderado signs with their own certificate
DEUC and declarations	Prepared for you	Your apoderado signs them
Offer in the PLACSP tool	Prepared and exported for you; a signed offer can be sent for you	Your apoderado imports and signs every document and envelope
UTE commitment	A lawyer drafts	Each member’s apoderado signs
AEAT, IAE and TGSS certificates	A gestor, asesor or graduado social, with their own credentials	Register their authorisation
Bid or performance guarantee	A bank, SGR or insurer issues and deposits it	Sign the facility
Sworn translations	A sworn translator on the Ministry of Foreign Affairs list	—
Contract signature	—	Your legal representative or apoderado signs

The professionals involved

Professional	Licensed or regulated by	What they do for a bidder
Abogado	Consejo General de la Abogacía Española; provincial Colegios de la Abogacía	Review the tender documents (PCAP, PPT); advise on admission, solvency, joint ventures and article 68; draft UTE commitments, reliance-on-capacity undertakings (article 75) and sworn declarations for you to sign; file the special appeal before the TACRC or a regional tribunal; act as your apoderado under a notarial power, signing with their own certificate
Notario	Consejo General del Notariado; Ministry of Justice	Grant the power of attorney naming who may sign bids, with the clause for the FNMT certificate; legitimise signatures and issue authenticated copies of corporate deeds; record declarations where a tender asks for one made before a notary
Gestor administrativo, graduado social or asesor fiscal	Colegios Oficiales de Gestores Administrativos; Consejo General de Graduados Sociales; asesores fiscales are not a regulated profession	Obtain your AEAT, IAE and TGSS certificates under a registered authorisation, using their own certificate; file modelo 036 and obtain a NIF for a foreign company; prepare accounts data for ROLECE and classification
Auditor de cuentas (ROAC register)	Instituto de Contabilidad y Auditoría de Cuentas (ICAC)	Audit the accounts behind your economic solvency; issue special reports on turnover or net worth when accounts aren’t deposited
Traductor-intérprete jurado	Ministry of Foreign Affairs, Oficina de Interpretación de Lenguas	Sworn translations into Castilian Spanish of foreign deeds, registry extracts, accounts, certificates, powers and works certificates
ENAC-accredited certification body	Entidad Nacional de Acreditación (ENAC)	Certify ISO 9001, 14001, 45001 and 27001 management systems, and conformity with the Esquema Nacional de Seguridad for IT contracts
Bank, SGR or insurer	Banco de España; Dirección General de Seguros y Fondos de Pensiones	Issue the aval or seguro de caución for the bid and performance guarantees, and deposit it
Tender consultant	Unregulated	Find tenders, read the documents, build the DEUC and technical document, prepare the offer in the PLACSP tool and export it for your apoderado to sign

If your company is from abroad

You don’t need a Spanish company to bid, though a works tender may require a non-EU winner to open a registered branch; who may bid from abroad, and on what terms, is explained in How to bid for public contracts in Spain. For the paperwork:

Capacity: EU companies give their home register extract (or a professional or trade register listed in Annex XI of Directive 2014/24). Non-EU companies prove capacity with a report from the Spanish embassy or consulate, which a lawyer requests with your apostilled documents and your representative signs.
Apostille: foreign deeds, registry extracts and powers need an apostille (Hague 1961) or consular legalisation; Regulation (EU) 2016/1191 exempts certain EU public documents.
Translation: a sworn translation into Castilian Spanish, or into the co-official language of the buyer’s region, by a translator on the Ministry of Foreign Affairs list.
Tax and Social Security: a company not obliged to file in Spain gives a sworn declaration instead of the AEAT and TGSS certificates, with home-country evidence if asked. Workers posted to Spain need A1 forms. IAE doesn’t apply without Spanish activity.
Accounts and references: home-country audited or filed accounts and client certificates, with sworn translations. Group companies’ solvency can be relied on with a written commitment (article 75).
NIF and signature: see steps 1 and 4: bidding with your home tax ID works, but signing inside the PLACSP tool then doesn’t.

Pitfalls

Never lend your certificate. PLACSP’s guidance says it in so many words: no se debe prestar el certificado electrónico. The export and import flow exists so that your apoderado signs on their own device.
Check the escritura before the bid. The apoderado recorded in the PLACSP tool must hold a sufficient notarial power, or be a registered administrator.
Watch the communications email. Notifications start legal time limits, so the address in PLACSP must be one you control and read.
Prepare the winner’s file early. Missing the 10-working-day deadline for documents and the performance guarantee counts as withdrawing your offer, with a 3% penalty (article 150.2 LCSP).
Keep ROLECE and classification current. Report changes and file the annual solvency declaration before 1 September, or face suspension and contracting bans.
Non-EU works bidders: for works of €500,000 or more you need your own Spanish classification; a UTE partner’s doesn’t cover you.
Foreign documents take time: the apostille and the sworn translation must be done before you file for ROLECE or classification, or send award evidence.
A lawyer can’t act for two competing bidders in the same tender: that is a conflict of interest.
Keep your auditor out of the bid. Under the independence rules of Ley 22/2015 de Auditoría de Cuentas, the auditor of your accounts can’t also prepare your bid.

Doing it with askTender

In Spain, your askTender Partner is added as a named user on your company’s account on PLACSP and works under their own login. You keep your own login, and sign what only you can sign: the notarial power, your certificate, the declarations, and every document and envelope of the offer through your apoderado. The askTender Desk prepares the DEUC and declarations, assembles the offer in the PLACSP tool and coordinates the certificates; askTender Partners, such as an abogado, a gestor or graduado social, or a sworn translator, do the steps their licence covers.

Questions

Which documents do I submit with a bid in Spain?

Declarations, not certificates: the DEUC (Spain’s European Single Procurement Document) or the buyer’s declaración responsable, which includes the declaration that you are not barred from contracting, plus your offer. Foreign bidders add a declaration accepting the jurisdiction of Spanish courts. Certificates and other evidence are asked only from the proposed winner.

Do I need an FNMT certificate to bid in Spain?

You need a certificate that the State’s @firma platform recognises, such as the FNMT legal-person representative certificate, which costs €14 plus taxes and lasts 2 years. The FNMT route needs a Spanish NIF for the company. A foreign company can use its own qualified certificate if it passes validation at VALIDe.

Can an adviser sign or submit my bid for me?

An adviser can prepare and upload the offer, and can perform the final send of an offer you have already signed. The signature itself must come from your apoderado, with their own certificate. A lawyer can be that apoderado under a notarial power, signing with the lawyer’s own certificate. PLACSP’s guidance says certificates must never be lent.

How long is the AEAT tax certificate valid?

Generally 12 months, unless your circumstances change, according to the AEAT. A tender’s documents may ask for a more recent one. Instead of sending it, you can authorise the buyer to consult it directly when you prepare the bid in the PLACSP tool.

What happens if I miss the 10-working-day deadline after being proposed as winner?

The buyer treats it as withdrawal of your offer, with a penalty of 3% under article 150.2 of the LCSP. The deadline covers both the winner’s documentation and the performance guarantee, so order certificates and line up the bank or insurer before the award proposal arrives.

Does a foreign company need a Spanish tax number to bid?

Not if it has no Spanish tax obligations: it can bid with its home tax ID, using the ‘Otros’ identifier on PLACSP. That route, however, doesn’t allow signing inside the PLACSP tool, and an FNMT certificate, ROLECE registration or classification need a Spanish NIF, which a gestor can obtain with modelo 036.

Sources

This guide explains the rules in plain English; it isn’t legal advice. Procurement rules change, and each tender document sets its own conditions — it always prevails.